2tablespoonsunsweetened cocoa powderor more to taste
2tablespoonschocolate-hazelnut spreadsuch as Nutella®, or more to taste
1/2teaspoonsalt
1/2teaspoonvanilla extract
Instructions
Stir self-rising flour, sugar, egg, vegetable oil, milk, cocoa powder, chocolate-hazelnut spread, salt, and vanilla extract together in a large mug until batter is smooth.
Cook in microwave oven on full power until the cake has risen in the mug and is set in the center, 1 1/2 to 2 1/2 minutes.